Expanded Polystyrene-Based Geomaterial with Fly Ash

This paper reports the engineering behavior of proposed expanded polystyrene-based geomaterial (EPGM) with fly ash through a laboratory experimental study. The proposed geomaterial is prepared by blending fly ash with expanded polystyrene (EPS) beads and a binder such as cement. The effects of different compositions and different mix ratios between EPS beads and fly ash (0.5-2.5%), cement and fly ash (10-20%), and water and fly ash (50 and 60%) on density, compressive strength, and initial tangent modulus of the geomaterial formed are studied. The authors observe that the density of EPGM can be effectively controlled by the quantity of EPS beads added in making the material. With the inclusion of merely 0.5-2.5% of EPS beads to fly ash (by weight), the density of the geomaterial formed can be reduced from 1,320to725kg/m3. The compressive strength of EPGM increases considerably if cement-to-fly ash ratios of 10, 15, and 20% are used. Compared with EPS block geofoam, EPS beads mixed geomaterial has higher density but higher compressive strength and higher stiffness. Thus the geomaterial developed in the current study can be used as a substitute for EPS geofoam block when strong fill materials with high strengths are required